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991.
The genetic mucopolysaccharidosis syndromes (MPS) are autosomal recessive inborn errors of metabolism. Heart valve involvement in MPS is not uncommon but only a few case reports of successful cardiac surgery are available. In particular, reports of combined aortic and mitral stenosis associated with MPS type I-S are very rare. Both type I and type VI MPS are associated with significant left sided valvar heart disease that requires surgical valve replacement because of irregular valve thickening, fibrosis, and calcification. A 35 year old man had severe mitral valve stenosis after successful surgical replacement of a stenotic aortic valve. Valvar heart disease was investigated by cardiac ultrasound and left heart catheterisation. Histomorphological characterisation of the affected mitral valve was performed. The case illustrates typically associated clinical features of cardiac and extracardiac abnormalities found in MPS type I-S. 相似文献
992.
目的观察塞来昔布在全髋关节置换手术进行超前镇痛的临床应用价值,为全髋关节置换手术围手术期镇痛优化提供依据。方法选择2015年3月至2018年3月在中国医科大学附属第一医院进行全髋关节置换手术的患者,共74例,随机分为观察组及对照组,每组37例。观察组口服塞来昔布3 d后进行手术,在手术后6 h继续给予口服塞来昔布3 d,术后同时给予静脉自控镇痛(Patient-controlled intravenous analgesia,PCIA)泵;对照组术前不给予镇痛药物,术后给予PCIA镇痛。观察两组不同时间点疼痛视觉模拟评分(Visual analogue scale,VAS)变化,记录PCIA按压次数,观察手术前后血清COX-2、PGE2水平变化及镇痛药相关不良反应。结果观察组术后离床时间早于对照组(P<0.05),观察组VAS评分在术后24 h、36 h及48 h低于对照组(P<0.05),观察组PCIA按压次数明显少于对照组[(3.27±1.09)次vs.(9.28±3.51)次,P<0.05]。观察组病人镇痛泵使用量明显低于对照组[(112.09±29.87)mg vs.(154.21±64.92)mg],差异有统计学意义(P<0.001)。与对照组比较,术后2 h观察组COX-2及PGE2水平均较低(P<0.05)。观察组与对照组术后烧心、恶心呕吐及眩晕等不良反应发生率比较差异无统计学意义(P>0.05)。结论塞来昔布在全髋关节置换手术进行超前镇痛可以减少静脉止痛药应用剂量,优化镇痛模式。 相似文献
993.
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995.
《Ultrastructural pathology》2013,37(4-5):475-479
A case of aorticopulmonary paraganglioma in a 57-year-old man is described. The tumor comprised nests of uniform cells in a fibrovascular stroma. Electron microscopy revealed abundant neurosecretory granules, and S-100 protein staining demonstrated scattered sustentacular cells at the periphery of typical zellballen. The findings in this case correlated with those of studies on the prognosis for extraadrenal paragangliomas. 相似文献
996.
Christopher Brown Lizeth Lacharme-Lora Blessing Mukonoweshuro Aman Sood Roger B. Newson John Fisher C. Patrick Case Eileen Ingham 《Biomaterials》2013
Metal hip replacements generate both metal particles and ions. The biological effects of peri-articular exposure to nanometre and micron sized cobalt chrome (CoCr) wear particles were investigated in a mouse model. Mice received injections of two clinically relevant doses of nanoparticles (32 nm), one of micron sized (2.9 μm) CoCr particles or vehicle alone into the right knee joint at 0, 6, 12 and 18 weeks. Mice were analysed for genotoxic and immunological effects 1, 4 and 40 weeks post exposure. Nanoparticles but not micron particles progressively corroded at the injection site. Micron sized particles were physically removed. No increase of Co or Cr was seen in peripheral blood between 1 and 40 weeks post exposure to particles. No significant inflammatory changes were observed in the knee tissues including ALVAL or necrosis. DNA damage was increased in bone marrow at one and forty weeks and in cells isolated from frontal cortex at 40 weeks after injection with nanoparticles. Mice exposed to the micron sized, but not nanoparticles became immunologically sensitized to Cr(III), Cr (VI) and Ni(II) over the 40 week period as determined by lymphocyte transformation and ELISpot (IFN-γ and IL-2) assays. The data indicated that the response to the micron sized particles was Th1 driven, indicative of type IV hypersensitivity. This study adds to understanding of the potential adverse biological reactions to metal wear products. 相似文献
997.
V. Gouilleux‐Gruart H. Chapel S. Chevret M. Lucas M. Malphettes C. Fieschi S. Patel D. Boutboul M.‐N. Marson L. Gérard M. Lee H. Watier E. Oksenhendler DEFI study group 《Clinical and experimental immunology》2013,171(2):186-194
Treatment of common variable immunodeficiency disorders (CVID) is based on replacement therapy using intravenous (i.v.) or subcutaneous (s.c.) immunoglobulin (Ig)G. Interindividual variation of IgG dose is common. A total of 380 CVID patients on stable IgG replacement from two prospective cohorts were analysed. An ‘efficiency’ index was defined as the ratio of serum IgG trough level minus IgG residual to the average weekly dose of IgG infusion. A reduced efficiency of IgG was associated independently with the i.v. route (P < 0·001) and with the presence of at least one CVID disease‐related phenotype (lymphoproliferation, autoimmune cytopenia or enteropathy) (P < 0·001). High IgG efficiency was noted in patients homozygotes for the variable number tandem repeat (VNTR) 3/3 polymorphism of the neonatal Fc receptor gene [IgG Fc fragment receptor transporter alpha chain (FCGRT)] promoter, and this was particularly significant in patients treated with IVIG (P < 0.01). In a multivariate analysis, FCGRT VNTR 3/3 genotype (P = 0·008) and high serum albumin (P < 0·001) were associated independently with increased efficiency of i.v. Ig. 相似文献
998.
Fatemeh Safara Shyamala Doraisamy Azreen Azman Azrul Jantan Asri Ranga Abdullah Ramaiah 《Computers in biology and medicine》2013
Wavelet packet transform decomposes a signal into a set of orthonormal bases (nodes) and provides opportunities to select an appropriate set of these bases for feature extraction. In this paper, multi-level basis selection (MLBS) is proposed to preserve the most informative bases of a wavelet packet decomposition tree through removing less informative bases by applying three exclusion criteria: frequency range, noise frequency, and energy threshold. MLBS achieved an accuracy of 97.56% for classifying normal heart sound, aortic stenosis, mitral regurgitation, and aortic regurgitation. MLBS is a promising basis selection to be suggested for signals with a small range of frequencies. 相似文献
999.
目的探讨心脏MR(CMR)定量技术纵向弛豫时间定量成像/心肌细胞外容积分数指数(T1 mapping/iECV)对主动脉瓣关闭不全(AI)患者的临床价值,并探索其与传统心功能参数的相关性。方法回顾性收集2012年5月至2016年2月在中国医学科学院阜外医院经影像及临床资料确诊为慢性AI患者36例。所有患者均接受CMR常规扫描序列、初始及增强后T1 mapping检查,CMR图像经后处理分析,计算主动脉瓣反流分数、钆对比剂延迟强化(LGE)质量分数、心肌细胞外容积分数(ECV)和iECV。基于CMR反流分数结果,将AI患者分为轻度组(9例)、中度组(14例)和重度组(13例)。3组AI患者初始及增强后T1值、ECV及iECV等计量资料比较采用单因素方差分析,进一步两两比较采用LSD检验;心血管相关病史、纽约心脏协会(NYHA)心功能分级及LGE阳性率等计数资料比较采用χ2检验或Fisher确切概率法;左心室常规功能参数LVEF与iECV的相关关系采用Spearman相关分析。结果3组AI患者年龄、性别、心血管相关病史差异无统计学意义(P均>0.05)。3组不同反流程度AI患者比较:(1)3组患者LGE阳性率总体差异有统计学意义(P=0.023),随着主动脉瓣反流分级程度增高,替代性纤维化发生率增加。(2)3组患者初始T1值、增强后T1值及ECV总体差异均无统计学意义(H值分别为1.815、0.929、2.496,P均>0.05)。3组iECV总体差异有统计学意义(H=16.725,P<0.001),重度组iECV值明显高于其他2组(P<0.05)。iECV与LVEF呈负相关(r=-0.649,P<0.001)。结论无创性CMR定量参数技术T1 mapping/iECV能识别不同反流程度AI患者发生弥漫性心肌纤维化的程度,并与传统心功能参数LVEF有较高的相关性,具有反映左心室功能失代偿前可逆阶段的潜力。 相似文献
1000.